Predator and CL could not provide any possible suspects.
Using Code Search for the file, "tree.c" assigning to the concern owner who might be related.

@dominicc -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

Automatically applying components based on information from OWNERS files. If this seems incorrect, please apply the Test-Predator-Wrong-Components label.

ClusterFuzz has detected this issue as fixed in range 506227:506265.

Detailed report: https://clusterfuzz.com/testcase?key=5561334312992768

Fuzzer: libFuzzer_libxml_xml_read_memory_fuzzer
Job Type: libfuzzer_chrome_ubsan
Platform Id: linux

Crash Type: Integer-overflow
Crash Address: 
Crash State:
  xmlStringGetNodeList
  xmlStringGetNodeList
  xmlSAX2AttributeInternal
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=450693:450724
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=506227:506265

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5561334312992768

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 5561334312992768 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.